Display device with a graphical user interface



The FIGURE is a front view of a display device with graphical user interface.

The outermost broken lines showing an electronic device illustrate environmental subject matter, whereas the remaining broken lines showing a display device and elements of the graphical user interface illustrate portions of the article. None of the broken line subject matters form part of the claimed design. 

CLAIM The ornamental design for a display device with a graphical user interface, as shown and described. 